Light‐Responsive Materials in Droplet Manipulation for Biochemical Applications

Abstract Miniaturized droplets, characterized by well‐controlled microenvironments and capability for parallel processing, have significantly advanced the studies on enzymatic evolution, molecular diagnostics, and single‐cell analysis. However, manipulation of small‐sized droplets, including moving, merging, and trapping of the targeted droplets for complex biochemical assays and subsequent analysis, is not trivial and remains technically demanding. Among various techniques, light‐driven methods stand out as a promising candidate for droplet manipulation in a facile and flexible manner, given the features of contactless interaction, high spatiotemporal resolution, and biocompatibility. This review therefore compiles an in‐depth discussion of the governing mechanisms underpinning light‐driven droplet manipulation. Besides, light‐responsive materials, representing the core of light–matter interaction and the key character converting light into different forms of energy, are particularly assessed in this review. Recent advancements in light‐responsive materials and the most notable applications are comprehensively archived and evaluated. Continuous innovations and rational engineering of light‐responsive materials are expected to propel the development of light‐driven droplet manipulation, equip droplets with enhanced functionality, and broaden the applications of droplets for biochemical studies and routine biochemical investigations.